DEVELOPMENT OF A FUZZY METHODOLOGY TO STUDY UNCERTAINTIES IN THE PROPAGATION OF A FLOOD WAVE, USING DATA OF THE POTENGI RIVER, RIO GRANDE DE NORTE- BRAZIL, AS STUDY OF CASE

Abstract

This research analyzes the flood wave propagation, checking how it can be used to evaluate uncertainties from the mathematical models, and input data. In such way, a mathematical model was formulated based on the hydrodynamic equations, jointly with the fuzzy set theory. The model developed is capable to evaluate the behavior of the control variables, as membership functions. To find the solution of the partial differential equations contained in the model, the Finite Differences Method was used. In order to get the solution of the nonlinear algebraic equations system, the Newton-Raphson Iterative Method was applied. From the results it can be observed that the use of the fuzzy set theory, in the hydrodynamic models, can become a viable alternative to evaluate uncertainties and, with that, to determine the risk of flood occurrences, in areas susceptive to flood waves propagation.

Key words: Fuzzy Set Theory; Hydrodynamic Model; Flood wave control.